Early enteral nutrition in the critically ill: do we need more evidence or better evidence?

Abstract

Purpose of review: Nutritional support of the critically ill is accepted as a standard of care. Recommendations for early enteral nutrition are based on reasonable evidence but only 50% of eligible patients receive enteral nutrition within 48 h of admission to the intensive care unit. The purpose of this review is to determine how recent developments advance the current state of knowledge.

Recent findings: The benefits of early enteral nutrition are supported by two recent evidence-based guidelines initiatives. Early (< 48 h after intensive care unit admission) enteral nutrition may decrease hospital discharge mortality by 8-12% (grade B+ evidence-based recommendation). Five recent level II clinical trials, two of which contain major methodological flaws, are consistent with this recommendation.

Summary: Higher levels of evidence, demonstrating benefit to a patient-oriented outcome, are more likely to change practice. The addition of more level II trials to a meta-analysis composed of level II trials may not convince clinicians to change practice. A level I trial (equivalent to a phase III Food and Drug Administration licensing trial) is required to convince more clinicians to provide early enteral nutrition. A level I trial would also provide an important opportunity to validate changes in disease-oriented outcomes (measures of nutritional status) against improvements in patient-oriented outcomes.